Since returning from the frozen harbor, the base has developed steadily with the help of new supplies, making significant progress in energy supply and infrastructure construction. However, Su Yao still keeps a close eye on the system's activity. She understands that in this endless, frigid world, only by continuously stockpiling supplies can everyone's survival and future hope be ensured.

That day, the system delivered an exciting message: Deep within the remote, frigid mountains lies a Phantom Ice Cave. It is said that the cave contains endless Phantom Ice Crystals. These crystals not only possess powerful energy, making them an excellent supplement to the base's energy core, but also have unique spatial properties, potentially resonating with Su Yao's spatial abilities to expand storage space even further. Furthermore, the cave may also conceal ancient cold-resistant treasures and long-lost ice-based ability cultivation methods—undoubtedly a godsend for them.

Without hesitation, Su Yao summoned Ling Yu and the cloaked figure. After a brief discussion, they embarked on the perilous journey to the Illusionary Ice Cave. The frigid mountains towered into the clouds, their slopes covered in thick layers of ice. A biting wind howled through the mountains, its sharp whistling sound like a death symphony played by nature itself. Along the way, they encountered countless avalanches and ice fissures. Ling Yu, with his superb ice-based abilities, repeatedly averted danger, clearing a safe path for everyone. The cloaked figure, meanwhile, focused intently on casting protective spells, ensuring everyone was spared the cold and unknown dangers.

After several days of arduous travel, they finally arrived at the entrance to the Illusionary Ice Cave. The cave emitted a ghostly blue light, and a layer of dreamlike mist permeated the area around the entrance, giving it a mysterious yet dangerous feel. Su Yao cautiously approached the entrance, attempting to use her spatial abilities to probe the situation inside, but a powerful counterforce instantly blocked her abilities.

“This cave seems to be protected by some kind of restriction, and my spatial abilities cannot explore it further,” Su Yao said, frowning.

Ling Yu gripped his ice sword tightly, his eyes resolute: "No matter what, we've come this far, we can't back down now."

The cloaked figure nodded in agreement, took out several rune stones from his bag, and handed them to Su Yao and Ling Yu: "These rune stones can temporarily enhance our defense and perception abilities, which may be of some help."

The three stepped into the cave, and as soon as they entered, they felt a bone-chilling cold wash over them, a cold that seemed to penetrate their souls and reach their very marrow. The cave walls were inlaid with countless illusory ice crystals that shimmered with strange light, as dazzling as stars in the night sky. However, just as they were captivated by the beautiful scenery before them, a swarm of illusory ice spirits emerged from all directions.

These illusory ice sprites, small in size like transparent crystal dolls, danced in the air, wielding tiny ice blades as they launched swift attacks. Ling Yu reacted quickly, brandishing his ice sword to form an ice shield in front of him, blocking the sprites' attacks. The cloaked figure chanted incantations, his hands forming hand seals, and golden runes flew from his hands, wrapping around the ice sprites and restricting their movements.

Taking advantage of this brief respite, Su Yao focused her energy on breaking the cave's restrictions. She closed her eyes and communicated deeply with the system, which guided her to discover the key nodes of the restrictions. Using her spatial abilities, Su Yao carefully interfered with and disrupted these nodes. After much effort, a portion of the cave's restrictions was finally broken, allowing her spatial abilities to be used successfully.

Su Yao quickly stored the surrounding illusory ice crystals into her system space, while simultaneously directing Ling Yu and the cloaked figure to advance deeper into the cave. As they went further, the dangers within the cave became increasingly severe. Frosty ice pillars would occasionally erupt from the ground, and huge chunks of ice would fall from the ceiling; they had to remain constantly vigilant to avoid injury.

Deep within the cave, they discovered a vast icy lake. In the center of the lake lay a small island, upon which stood an ancient ice tower. Su Yao sensed that the ice tower contained immense power and precious treasures. However, the icy lake was surrounded by powerful magical traps; a single misstep could lead to utter destruction.

Ling Yu stepped forward, maximizing his ice-based abilities to create a sturdy ice bridge across the frozen lake. The cloaked figure then arranged rune arrays around the ice bridge to enhance its stability and safety. Su Yao followed behind them, carefully crossing the ice bridge and heading towards the ice tower.

As they stepped into the ice tower, an ancient and powerful aura washed over them. Inside the tower lay a massive treasure chest, surrounded by a powerful ice-magic shield. Su Yao attempted to analyze the shield's energy structure using her system, and after some effort, she found its weakness. Following Su Yao's instructions, Ling Yu and the cloaked figure launched a full-force attack on the shield's flaw. With the three working together, the shield was finally breached.

Opening the treasure chest, she found it filled with precious items. Among them was an ancient manual for cultivating ice-based supernatural abilities, which Su Yao handed to Ling Yu, hoping he could use it to improve his strength. There were also several suits of ice armor radiating powerful cold-resistant properties, and some mysterious gems that could enhance spatial stability. Su Yao carefully stored these treasures into her system space, her heart filled with joy and anticipation.

Just as they were about to leave the ice tower, it suddenly began to shake violently, as if it were about to collapse. They rushed towards the exit and managed to escape just before the ice tower completely collapsed.

After leaving the Illusionary Ice Cave, they began their journey home. Although the expedition was fraught with hardship and danger, the rewards were immense. These supplies would bring new development opportunities to the base, giving them greater confidence and strength in their fight against the extreme cold. Su Yao knew that the road ahead to stockpiling supplies would still be long and challenging, but she was fearless. She firmly believed that as long as they remained united and continued to explore and strive, they would surely be able to safeguard the light of hope in this apocalyptic world and pave a bright path for humanity's future.